Formation of nanoparticles from laser irradiated Au thin film on SiO2/Si: Elucidating the Rayleigh-instability role

Nanosecond laser irradiations were used to induce a dewetting process of a thin Au film on SiO2/Si. The melting and solidification dynamics of the film under the irradiations lead to a dewetting process whose driving force was identified in a Rayleigh instability mechanism. Such a mechanism determines the formation of Au nanoparticles from the melted quasi-continuous starting Au film. The mean nanoparticles size and spacing were quantified, finding their correlation as described by the surface-diffusion-limited Rayleigh instability theory.

Graphical abstractFigure optionsDownload full-size imageDownload as PowerPoint slideHighlights► Dewetting process of Au thin film on Si is induced by laser irradiations. ► Rayleigh instability phenomenon is found to drive the dewetting process of Au on Si under laser irradiations. ► Mean Au nanoparticles size and spacing are quantified and related as a function of the laser fluence.